MONTHLY REVIEW

Published
by the
American Electroplaters Society
Publication and Editorial Office
3040 Diversy Ave., Chicago

VOL.
XVII SEPTEMBER, 1930 No. 9

EDITORIAL

Now that the vacation season is over, and the various branches
are again taking up the activities which have been dispensed with during
July and August, it might not be out of order to remind our readers that
the Electro-Platers Society expects this year to be an unusual one.

First
of all there should be a great revival of interest in the Branches.
There are hundreds of foreman platers who are not being reached by our
Society. These men are in sympathy with us but are not a part of us.
Every member beginning now should try to encourage all platers who
are
eligible for membership in the A.E.S. to become affiliated with our
organization. Personal invitation to non-member, boosting the work of
the Research
Committee, or passing on your Monthly Review after it has been read
are all means of bringing new recruits into our ranks, and are influences
which help the plater who needs our help.

The Research Committee with
Mr. Jacob Hay as Chairman should have the enthusiastic support, both
moral and financial, of every plater and his
employer. The work at the Bureau of Standards under Dr. Blum’s
able leadership must be carried on. Our hearty co-operation and enthusiasm
will go a long way towards making the tasks of the newly appointed Research
Committee successful.

The Bureau of Education is to become a very
vital factor in our branches this year. Mr. Albert Hirsch of Philadelphia
Branch
has recently been
appointed chairman by President Gehling and is well qualified to bring
the Bureau out of oblivion and make it ”go to work.” Every
Branch should feel the influence of the Bureau of Education’ as
each society will have a representative who will be able to keep in touch
with the Chairman of the Bureau and by this method it is hoped more interesting
and educational sessions will be held than we have had heretofore.

Platers
Classes—Well, a whole page is at your disposal, branch
secretaries, so when you have anything to report concerning the classes,
just see if you can crowd the page. And in this connection, note all
items of interest in your branch and send them in.

Associate Editors—There
is always room in this Review for papers valuable to our membership.
Will you not forward any such matter that
may come into your possession, so that we can keep up to date and make
this publication both interesting and instructive?

Next month we hope
to hear from the Boston, Dayton, Grand Rapids, Cincinnati, Indianapolis,
and Worcester Branches. Let’s make the October REVIEW
100% by having a report from every Secretary.

THE DEPOSITION OF NICKEL
AT A LOW pH

Our
interest in pH in nickel solutions dates from the Letter Circular No.
82, issued by the
Bureau of Standards, October 10, 1922, and the
paper on this same subject in the Transactions of the American Electro-chemical
Society, Vol. 41, 1922, page 333, by W. R. Thompson, ”Acidity of
Nickel Depositing Solutions.” In this bulletin it was recommended
that the pH be kept at about 5.7 and the statement was made that practically
all satisfactory nickel plating is conducted in solutions with a pH between
5.4 and 6.3. Our plants as well as the electro-plating industry in general,
followed these recommendations and for several years a pH of 5.7 was
considered to be both satisfactory and necessary. Very careful measurements
had to be made because a variation of even 0.1 pH came to be considered
as very serious.

However, one of our production plants found that additions
of sulphuric acid gave them better results, and, due to inaccuracies
in determining
pH, it was thought that the bath was being maintained at about 5.2.
This value was just below that at which the indicator (brom cresol purple)
would operate, and since excellent results were obtained, the matter
was not investigated further. The improved quality of the work attracted
attention to this plant, and at the same time laboratory work which
had
been started in our laboratory from theoretical considerations, indicated
the desirability of low pH. In the course of a routine checking of
the analyses of the nickel plating baths being used throughout our Corporation,
it was found that the bath at this plant where the superior results
were
being obtained had gradually been lowered until it was 2.5.

This
discovery caused consternation, and threw grave doubts on the ability
of our laboratory
to determine pH values, which only goes to show how
firmly high pH was intrenched in everyone’s mind. However, immediate
and careful checks in several laboratories using the quinhydrone electrode
as well as colorimetric methods showed that the low pH values were correct.
The low pH of the solution from the plant obtaining the good results
was the only marked difference in the analyses of the solutions from
the different units of the Corporation. This production experience which
checked our laboratory findings, stimulated activity on this subject.

At
this point we wish to emphasize that we are interested in low pH solutions,
not because they are low, but because we are interested in better plating.
The advent of rustless iron and stainless steel makes it necessary
for the plating industry to greatly improve the quality of its work if
it
expects to survive. One of the best ways to improve is to put on a
heavier plate, but with the high pH solutions this is difficult or impossible
except at a great sacrifice of time, since the high pH solutions require
low current densities. By the use of low pH solutions the current density
can be greatly increased and the thicker plates that are required for
durability may be deposited.

In this paper, we will endeavor to present
the advantages and disadvantages of low pH solutions for nickel plating.
Briefly, they are as follows:

ADVANTAGES

Increase in plating range.
It is possible to use a higher current density without peeling or cracking
at the edges.
The decreased time due to the use of the higher current density permits
a better use of the equipment.

Better anode corrosion. (Shows used
anodes.) That is all that is left of an anode in a low pH bath.
(Showing dagger-like anode.) You will notice you can bend that pretty
easily,
and break it, of course. At this particular plant, they are not
satisfied with that kind of scrap, so they weld them all together and
use them
up entirely in that way. So they save everything but the squeal.

No
turbidity in the bath if the pH is kept sufficiently low (below
about 3.0).

The nickel is supplied to the solution from the anodes
instead of by the addition of nickel salts, thus giving lower costs.

DISADVANTAGES

There is a greater initial tendency for
a low pH bath to cause pitting.

Lower cathode efficiency.

Too high anode corrosion
under some conditions.

Trouble will result if the pH is allowed to
become high.

There is a tendency for the pH to increase gradually,
thus making it more difficult to control pH values.

Since it is desirable
to operate the low pH baths at high temperatures, the tanks and
linings are restricted to materials
which will permit
such temperatures.

For bright nickel plating the low
pH bath gives best results at low temperatures while the high pH
bath can
be operated
over a wider
temperature
range.

The low pH bath is not suitable for plating zinc base die
castings.
It might be desirable to discuss these advantages and disadvantages
in detail.

ADVANTAGES

Increase in plating range.
It is possible to use a higher current density without peeling or cracking
at the edges. This means that pieces of irregular shape can be plated
rapidly and satisfactorily. In addition, a thicker plate can be obtained
within the permissible time limits. With either regular or irregular
shaped pieces, more work with a definite thickness can be done in unit
time, and less tanks, solutions, and floor space are required. The decreased
floor space makes it possible to use shorter and thus cheaper conveyors,
giving a saving in labor and an increase in production.
Four sets of curves are given to illustrate this wider plating range
possible with low pH. Curves ”a” and ”b” are
based on a 5 minute plate on copper. These curves give data which may
be used when a short plating time is used. For example, with a pH of
1.0 they show that even when the irregularity of the pieces is such that
the current density between different areas varies as much as from 150
amps. per square foot to 10 amps. per square foot, a 5 minute plate at
any temperature above 125° F. will give a good deposit. However,
if the pH should be 5.0 and the temperature should be the same, that
is, 125° minimum, the current density must not be over 28 amps.
per square foot on the high spots or burning, peeling and cracking
will occur.
At a pH of 6.0 the maximum current density appears to be about 16 for
the same temperature range.
Curves ”C” and ”D” show the relations for current
density and temperature for different pH solutions when it is desired
to obtain a plate .0005” thick on a flat surface such as a test
panel. It will be noted that when a pH of 6.0 is used it is almost impossible
to obtain a deposit .0005” thick without having the plate burned,
cracked or peeling.
There is a marked difference between results obtained at pH 6.0 and
those at pH 5.0 when heavy deposits are required, but the greatest
gain is
made at a pH of 2.0 or lower.

Better anode corrosion.
The low pH solutions give much better anode corrosion. It may be
possible to change the solutions in other ways to secure similar
results, but
the fact remains that with low pH solutions of the conventional
type the problem of corrosion of the anodes practically disappears.

No turbidity
in the bath if the pH is kept sufficiently low. This critical value
is about 3.0. All platers are familiar with the turbidity
in ordinary nickel plating baths with the resultant sludge. With
low pH bath, this is entirely eliminated except perhaps in the case
of
high carbon anodes. It is not claimed that low pH solutions will
dissolve free carbon.

The nickel is supplied to the solution from the anodes
instead of by the addition of nickel salts, thus giving lower costs
since nickel
in the form of anodes is much cheaper than nickel in the form of
salts. Records in production show that one of our plants has been operating
with a low pH bath of 9000 gallons for at least eighteen months
without
having to add any nickel salts. The loss due to drag-out is taken
care of by nickel from the anodes, together with additions of free
sulphuric
acid.

DISADVANTAGES

There is a greater initial tendency for a low pH bath
to cause pitting. This may be due to an increase in the rate of
solubility of the impurities
in the anodes, sludge, cracks and corners of the tanks, tank linings,
anode supports, etc. After the bath once gets adjusted we do not
believe that there is any relation between pH and tendency to pit.
Our records
show that one of our production plants which has the most trouble
from pitting is still operating on the old basis of high pH, and the
plant
which has been using low pH for about 18 months is relatively free
from pitting troubles.

Lower cathode efficiency.
In general the high pH baths give cathode efficiencies of about 93
to 95% and the low pH baths give lower efficiencies, reaching
as low as
about 7070 for a pH of 1.0. This loss in cathode efficiency does
affect current cost and generator cost but we do not consider this
as a serious
objection, and we feel that the savings due to low pH many times
offset this small loss.

Too high anode corrosion under some conditions. Most
platers worry about getting the anodes to corrode fast enough.
It is apparent that
with the rapid corrosion of anodes with low pH baths there might
be a tendency to accumulate too much nickel in solution. The drag-out
tends
to correct this excess and other means such as regulating the anode
area
will control it.

Trouble will result if the pH is allowed to become
high. Adoption of the low pH will enable the plater to get out
more work and better
work. If through inattention he allows the pH to rise he will find
himself in trouble and plenty of it. He will be trying to obtain
the advantages
of a low pH bath with an old fashioned high pH bath, and this is
difficult if not impossible.

There is a tendency for the pH to increase gradually,
thus making it more difficult to control pH values. This is more
of an imaginary
trouble than a real one for the low pH baths do not have to be
controlled so closely. Instead of worrying about tenths of a pH the
plater considers
units. Where formerly a change of from 5.7 to 5.9 was considered
as serious, the limits for a low pH bath would be somewhere between
1.0
and 2.5 or
thereabouts. The excellent work of the Bureau of Standards on accurate
determinations of pH values is more or less wasted on the nickel
plater using low pH baths.

Since it is desirable to operate the low pH baths
at high temperatures the tanks and linings are limited to materials
that will permit such
temperatures. However, high pH baths should also be operated at
high temperatures and so this objection loses most of its weight.

For bright
nickel plating the low pH bath gives best results at low temperatures,
while the high pH bath can be operated over a wide temperature
range. This is shown by the charts A and B. 8. The low pH bath is
not suitable for plating zinc base die castings. This is a valid objection
to the low pH bath, but at the same time we would appreciate it very
much if someone would show us a bath that is entirely satisfactory
for
nickel plating zinc base die castings.
We have tried to present in a brief manner the advantages and disadvantages
of low pH nickel baths, but we recognize that much work remains to
be done. We believe that with the co-operation of the American Electro-platers’ Society
great strides can be made in the near future in improving nickel
plating.

(See
charts on following pages.)

MR.
R. W. MITCHELL: I would like to ask a question—what effect
the low pH has on the physical properties of the deposit?

MR. PHILLIPS:
Well now, in order to answer that, I would like to have these panels
themselves. We brought the evidence right here with us.
We have the actual panels.
(Exhibits cards of panels from which data for the preceding curves
had been drawn.)

MR. MITCHELL: With that high degree of acidity, do you
have to take any precautions of mechanical agitation and so on to get
hydrogen
bubbles
off of your cathodes?

MR. PHILLIPS: No, sir. This work has been done in
a practically still bath.
Now these cards with the actual panels on them are the basis of those
charts that you have, and they are physical proof of those charts. That
is, you can see that the deposits are good where we say they are good
by looking at those. You will see up there at 6.0 that the range is very
narrow, and I may say that the bottom half of each of these panels is
chromium plated. Now the reason for chromium plating that is that it
is a pretty good test for the plating itself. If it won’t stand
chromium plating in these days, we are not much interested in it. So
we chrome plated the bottom half.

You will notice right along there that
this narrows out, there is a very narrow range in 6, better in 5, better
in 4, better in 3, better in 2,
and look at the range here in 1. We got good plates all the way through
there, almost, down to here (indicating panels). You will notice that
cut-off there is just like the cut-off on your curve.

Now
I just want to call something to your attention. You may say a panel
is theoretical.
A panel isn’t so theoretical, either; a panel is
pretty hard to plate. That is, you are going to get quite a variation
of distribution of current on a panel. Lots of things you plate in the
plant are easier to plate than panels.

A paper by Schneiderman some time
ago gave distribution of current for chromium plating, and it applies
almost equally as well for this. This
sketch indicates the current density at the different sections of a
panel, as ascertained by actual measurement. So that you see that these
panels
are not favoring the thing very much.

DR. BLUM: Were the panels plated
in large or small tanks?

MR. PHILLIPS:
In small tanks.

DR. BLUM: Have you any data, Mr. Phillips,
on the protective value of these coatings, porosity and so on?

MR. PHILLIPS: I would say that we
have. We have a Florida rack at Miami, Florida, where we send all kinds
of plated and painted and enameled goods
for test. That is a pretty severe test. Well, in an effort to find
out what plates were best, we sent plates from all divisions, including
a
lot of these low pH panels down there on a couple of occasions. On
both occasions, these panels came back perfect. At the same time, we
tested
similar panels in both salt spray and calcium chloride. The salt spray
test, as I remember it, went over 230 hours on panels that were plated
through this production tank, and showed no tendency to porosity. They
also stood up very, very well in the Florida climate which is pretty
hard on everything.

MR. GEORGE HOGABOOM: Will you explain the calcium
chloride test?

MR.
PHILLIPS: Well, now, the reason for using calcium chloride is merely
this, that
calcium chloride is used in the winter in some States and
cities to melt ice and snow. It is pretty hard on the plating, pretty
hard on the paint and enamel, and we therefore thought it would be a
good idea to test some of this work with calcium chloride, so we set
up an intermittent calcium chloride spray; that is, it was sprayed for
a certain time, then left stand for a certain time and sprayed again.
But here is the sad part of it. Neither the salt spray nor the calcium
chloride in any way checked our Florida results, except that we got this
extremely long test in the salt spray, over 230 hours, on the panels
that stood up so well in Florida: but the ones where the decision was
closer, we didn’t get any coordination with either calcium chloride
or the salt spray with the weather test.

DR. BLUM: Is the use of calcium
chloride for dust settling objectionable?

MR.
PHILLIPS: We do not so consider it. When it is used for settling dust,
the material sinks into the road bed. When used for melting ice,
it stays on top and forms a solution that readily splashes.

MR. GEORGE
HOGABOOM: Can you make the calcium chloride test with the same apparatus
used for the sodium chloride test?

MR. PHILLIPS: Yes.

MR. R. W. MITCHEL: Suppose, in the highly acid bath,
you wanted one plate to be very hard for abrasion resistance, and another
plate to be quite
soft and ductile. Could you control the physical characteristics of
the plate in any way to get the desired results?

MR. PHILLIPS: I would say
the temperature of the solution would give you a degree of control.

MR. HARVEY GAUSING: What was the metal concentration
of this solution carried at a low pH?

MR.
PHILLIPS: On the chlorides, we are not definitely set; it is something
we have to determine. We have got these
baths operating
both with low
chlorides and relatively high, both successful, and we don’t know
exactly on the chlorides; but there does seem to be an advantage in running
the single salt content up perhaps as high as forty ounces.

MR. GAUSING:
That is single sulphate?

MR. PHILLIPS: Yes.

MR.
J. H. HOEFER: IS there any other method than the quinhydrone electrode
for determining these low pH’s?

MR. PHILLIPS: Yes, you can get colorimetric
sets that go down that low.

MR.
HOGABOOM: I am wondering if the question of pitting isn’t associated
with the deposition of the metallic impurities that may be in the bath
in the original state. Remember the work that was done by Fink and Rohman
and presented at the last meeting of the Electrochemical Society at St.
Louis? When they wanted to get a perfectly pure nickel deposit, they
used a pH of about 2. And in the discussion, Dr. Fink admitted that they
had excessive pitting when they were depositing out the copper. Now in
copper refining, when the nickel comes to a certain concentration, it
will be deposited. When you have these metallic impurities like iron
and copper in this bath, when they come to a certain concentration, is
there a possibility there would be either a cementation or electrodeposition
and that would cause pitting and when the concentration has been decreased,
why your pitting stops. And also that when you add such a thing as hydrogen
peroxide, you change the cathode polarization, and therefore stop the
deposition of those metals until that hydrogen peroxide has lost its
value, and then they begin to pit out again? And isn’t that one
of the reasons why there seems to be a necessity as the bath grows older
to increase the amount of hydrogen peroxide that must be added to keep
that bath from pitting?

MR.
H. C. MOUGEY: With our low pH baths we do not increase the hydrogen
peroxide,—it gets less and less.

MR.
HOGABOOM: That would bear it out, because as you get out your impurities,
then the metallic impurities
in there wouldn’t have such an effect
on pitting, and therefore the addition of hydrogen peroxide would be
eliminated, because hydrogen peroxide would only be added to change the
polarization of the cathode so as to prevent those impurities. Now if
those impurities are plated out in the beginning, then the necessity
of using hydrogen peroxide would be greatly increased, and that bears
out your experience.

MR. PHILLIPS: It does exactly. Now I may say we used,
when we started this low pH bath, 300 gallons of peroxide in a 9,000
gallon bath in two
weeks. That has gotten down to a point where 300 gallons would last
us for at least three months, if not very much longer. We use very little
peroxide at the present time.

MR. HOGABOOM: I would like to ask Mr. Maugey
another question. If there is iron in the solution, suppose you use
sodium perborate. Is that better
than hydrogen peroxide, or as good?

MR. MAUGEY: Mr. Phillips can answer
that.

MR. PHILLIPS: The use of sodium
perborate was effective in preventing pitting, but we do not believe
that the continued use of sodium perborate
would be so very good in a low pH bath, or perhaps any other bath,
on account of the increasing amount of sodium in the bath. We would rather
perhaps get a little less effect with hydrogen peroxide than continue
to use sodium perborate in the bath.

DR. BLUM: It might be well, Mr. Phillips,
to emphasize a point you already brought out that a bath of this kind
is self sustaining in the sense
that the term has been used by some platers; in other words, that you
are getting your metal from your anodes. That means, then, all the
more, the importance of using pure nickel anodes, even though, as you
say,
this solution will corrode anything except carbon. That very fact means
that you want to have pure nickel anodes; otherwise you will be dissolving
all your copper, iron, and everything else that is in them, so that
it would look to me as if the purest nickel anode you can get would be
especially
desirable for this type of solution, because you do not have to add
any nickel salts, and therefore if you can control the anodes you can
certainly
get pure sulphuric acid and consequently you are not adding additional
impurities to the solution from time to time.

MR.
PHILLIPS: That is certainly quite true. You don’t want to take
advantage of this bath to buy cheap nickel anodes just because they will
corrode. If you do, you will probably ruin your nickel solution after
a while. Take advantage of it, rather, to dissolve the purest and best
anodes you can get because you can dissolve them. You can dissolve even
cathode nickel in good order.

MR. PEARSON: What current density do you
use for work in general with this solution?

MR. PHILLIPS: About 35 or 40 amperes per square foot has
been our general practice.

MR. PEARSON: And about how long does it take a new solution
before it works satisfactorily?

MR. PHILLIPS: That is an awfully tough question,
that last one. We have only been through that a few times. It took
us about two months to get
what we really considered a satisfactory product out of one of these
baths. But we believe we can do it in a shorter period next time.

MR.
HOGABOOM: Have you tried purifying your bath previous to using it?

MR.
PHILLIPS: No, we haven’t. We took the bath pretty much as it
was, and then made it worse, for this reason. We had a coil made of a
certain trade name bronze which I won’t mention, but that coil
dissolved in our bath, and that didn’t particularly help things.

MR.
WM. GRUND: In putting chromium deposits over this range, that is, 1
and 2 pH on this nickel, does the current density have to be reduced
to keep that coating from lifting off?

MR.
PHILLIPS: NO, YOU can increase it very materially. I would say that
is one of the big advantages, that
your deposit will be a better deposit
for withstanding such chromium deposits. I don’t believe we would
have done it if it hadn’t been for chromium.

MR. JAMESON: You spoke
of not using sodium perborate on account of the sodium building up
in the solution. Just what is your objection to sodium,
and furthermore, do you or do you not use sodium chloride in the first
place as a means of introducing chloride in your bath?

MR.
PHILLIPS: I will answer your last question first. We don’t
use sodium chloride to introduce chloride. We use nickel chloride. And
the reason we don’t want to put sodium in the bath is we don’t
know what sodium will do. We know we can work without it; we don’t
know whether we can work with it or not, so we are not going to put it
in.

MR.
G. B. HOGABOOM: Isn’t it true
that a bath containing sodium chloride has a greater tendency to run
to alkalinity than one which contains
nickel chloride, and may there not be some effect at the cathode where
you get more alkaline film?

MR.
MAUGEY: That is one of the theoretical reasons that made us start to
work on the elimination of sodium, and
we found with certain baths
we would get pitting when we added sodium, and we could eliminate the
pitting by leaving out the sodium. But we aren’t positive now that
sodium is as bad as we once thought it was, but we know that we can get
along without it, and prefer to be without it.

MR. HOGABOOM: Would the
pitting be accompanied with precipitation of nickel hydrate rather
than gas pitting?

MR.
MAUGEY: No, it doesn’t
seem to; it just seems to cause pitting on the work.

MR. PHILLIPS: Mr. Maugey, there seemed to be a relation
between the presence of ferrous iron and sodium in those first experiments.
That
is, where
we had both ferrous iron and sodium, we got a great many more pits
than if we had either one by itself.

MR.
HARVEY GAUSING: Do you experience any more pitting in this low pH solution
after a shut-down of a day or
two?—The solution getting
cold, and then warming it up again, say over Saturday and Sunday? Do
you experience pitting then more than from one day to the next

MR.
PHILLIPS: Not as much. That is an experience we have constantly with
the high pH
baths, but we don’t have that same experience with
the low pH baths. Our shut-downs don’t seem to bother us very much.

MR.
JAMESON: It seems rather strange to hear of pitting in a nickel solution.
I have used common ordinary salt for the last three years in a 6,000
gallon bath, and pitting is certainly unknown in our plant. Now this
idea of adding nickel chloride because you don’t want the sodium
element in there,—if you consider it a fact that you are buying
nickel chloride, I think it is about 40¢ a pound, and only 20% available
chlorine present in it, whereas you can buy common salt at 3¢ a
pound, and about 50% of which is available chlorine. I can’t just
reconcile the fact that sodium is responsible for the pitting, because,
as I said, we never have any. When I say ”never,” I may be
exaggerating, but we don’t have any pitting to speak of; have not
had for the past three years.

Now
we do add a certain amount of sodium perborate in our nickel tanks
every night, and we also add a certain
amount of hydrochloric acid to
our tanks every night to be sure we don’t experience any pitting
the next day. I would like to hear something said about that.

MR.
PHILLIPS: Mr. Jameson, the whole thing is this. Perhaps we were more
cautious than
we had to be. But when we have a 9,000 gallon bath and
the total production of the plant to contend with, we would rather spend
a little money just to be extra careful. We don’t know that sodium
chloride would put us in trouble, but we know that we are playing it
safe when we don’t put any sodium radical in, and that is the reason
for doing it. The other thing may be perfectly all right.

MR.
B. G. DAW: Do you find the deposit more uniform on irregular parts
than with the
higher pH solution?—Better throwing power, in other
words?

MR.
PHILLIPS: Those panels demonstrate that very nicely; that is when you
realize for instance that this 1.0 pH
panel, and by
the way
we haven’t
called your attention to the fact that these second cards we put up here,
we plated half a thousandth on those, instead of plating for five minutes
as we did in the other series. But you are going to have a very much
wider range. Now your irregular object burns and peels on the edges simply
because you have a current concentration on those edges. Well, if you
can plate from we will say 50 amperes to 150) you will be pretty sure
then that those edges won’t burn. If you can only plate from we
will say 10 to 20, you can be pretty sure they will burn.

MR.
FERRIS: Those samples that were sent to Florida for test,— were
they plated directly on steel, or nickel, copper and nickel?

MR. PHILLIPS:
We tried all kinds. Not all programs, but all the programs in use in
the different divisions of General Motors. Some were nickel
copper and nickel, some copper and nickel, and so on, the different
kinds.
Possibly a rather interesting thing, without taking too much time,
is that we had two panels, two sets of panels that came through very
well.
They both had about one thousandth of an inch deposit, about a thousandth
and a quarter of deposit. In one case the panel was 50% copper and
50% nickel, and about twenty-five millionths of an inch of chromium,
and
the other one was only about 10% copper, and almost a thousandth of
nickel, and the same amount of chromium, and they were both good panels,
but
there was about a thousandth of deposit on both of them, which makes
this old thousandth look pretty good.

MR. R. F. CLARK: May I ask if you
advise a low pH in a plating barrel which has a horizontal cylinder?

MR. PHILLIPS: I regret to say we have
done no work on the plating barrel with low pH baths.

Question: Have you made any measurements on the actual
cathode efficiency? That is, you said the cathode efficiency is low.
I was wondering what
that would be.

MR.
MAUGEY: We made many measurements on cathode efficiency and the cathode
efficiency does drop as the pH drops,
but the cathode
efficiency even
on the pH of 1.0 is about 70%, so we don’t believe the cathode
efficiency is a real factor in our work.

DR.
BLUM: That question of cathode efficiency is tied up with a previous
question which you didn’t
quite answer on throwing power, distribution of deposit as distinguished
from the question of whether the deposits
were good or not. If the cathode efficiency is low, but uniformly low,
you will still get good throwing power. If, however, it is low and drops
off more rapidly at that low current density than a high pH solution
does, you will get poor throwing power. How do you know which is the
case?

MR. PHILLIPS: We have never made any throwing power measurements.
We only know we can plate the pieces we have to plate, that is all.

MR. MAUGEY:
We have to plate them with chromium, and chromium is very difficult
to throw. Therefore when working with nickel it throws very
much better than chromium, so we never got interested in the possible
differences in throwing power because we have to plate them all with
chromium anyway.

Question: On these curves here, there is no mention made
of the amount of nickel sulphate carried in the solution. Now certainly
there is going
to be a difference if you run one of these curves with 16 ounces of
nickel sulphate and another one at 32 ounces of nickel sulphate.

MR. MAUGEY:
Those are all the same in nickel sulphate. They are the Watts bath,
the standard Watts bath, 32 ounces of nickel sulphate.

MR. PHILLIPS:
And I may say at 40 ounces in a production plant that the results at
least are very comparable.

MR. G. A. WILSON: I want to ask
if you maintain running the bath sixteen or eighteen months?

MR. PHILLIPS: Yes.

MR. WILSON: Without the addition of any chemicals?

MR.
PHILLIPS: I wouldn’t
say no chemicals, but no nickel.

MR. GAUSING:
Would you use commercial sulphuric acid to maintain the acidity of
this solution?

MR.
PHILLIPS: You could use commercial sulphuric acid. Frankly, we don’t.
We buy pure sulphuric acid for the job. We are just over-cautious, perhaps.
Maybe in a year or two we will broaden out a little bit.

MR. GAUSING:
You have never used any hydrofluoric acid?

MR.
PHILLIPS: No, sir, we couldn’t. We have in some cases lead
lined tanks and couldn’t use that.

MR. JAMESON: How about hydrochloric
acid?

MR.
PHILLIPS: Well, hydrochloric acid, of course, might be used. We haven’t
done any work on it.

MR.
WM. SNYDER: Has any thought been given to any other acid than those
mentioned here for additions?—such
as phenol or some other acid?

MR.
PHILLIPS: Well, getting back to Mr. Pitschner’s paper on this
buffing, we had thought of using an acid such as perhaps acetic acid
as a buffer for these lower pH baths so as to prevent shifting around
too much. We haven’t, for the purpose of reducing pH, particularly,
thought of any other acid.

MR. MAUGEY: Yes, I might say that was one of
the things that prompted this work in the beginning. We used a nickel
acetate bath, and acetic
acid, and got these wonderful results with low pH. And that was one
of the things we wanted to find out, why we got those good results, and
we found we got those good results with any bath as long as we had
the
pH low.

Question: We
didn’t hear
what the lining of your tank was. Is it tar or asphalt?

MR. PHILLIPS: Rubber. The biggest operation we have is
in a rubber lined steel tank.

Question: And your heating element, what is that made of?

MR. PHILLIPS:
The heating elements are of lead pipe.

MR.
WM. GRUND: Speaking of chloride, is there any way of dissolving enough
nickel chloride in
a nickel solution, we will say where the pH changes
at the rate of from 5.8 to 6.4, in a matter of three or four hours,—is
there any way of dissolving enough nickel chloride or putting it in solution
to get quick action in the results? I might leave that for Mr. Hogaboom,
to answer that question.

MR.
HOGABOOM: I can’t see the necessity
of using nickel chloride for correcting the pH.

MR. GRUND: I thought that was the way this man
made the remark they used nickel chloride.

MR.
PHILLIPS: The favorite use of the chloride has been to promote anode
corrosion. I don’t think it is put in for any
other purpose particularly; and our experience with this low pH is that
we are at this time doubtful
as to how much if any chloride we need. We just don’t know. It
is possible we don’t need any.

Well, we have certainly had a lot
of discussion.

CHAIRMAN VAN DERAU: I
believe in another year this is going to be a very active subject.
I think we owe Mr. Maugey and Mr. Phillips a rising vote
of thanks for the way they brought this up at our Convention.

(Rising
vote extended)

PRACTICAL
LACQUER EVALUATION FROM THE PLATER’S
STANDPOINT

BY R. V. Kirk
Read at Washington Convention, 1930

The object of this paper is to suggest
to the plater who uses lacquer means by which he may, in a quick and
empirical, yet practical way, test
and evaluate the many lacquers offered for his use.

The plater with a
well equipped chemical laboratory at his disposal will have less need
for these suggestions than will his less fortunate brother,
who is forced to depend on the usual plating shop equipment to test
his lacquers. However, these tests, performed as they are simply with
ordinary
shop equipment, may not only serve to augment the regular physical-chemical
laboratory tests, but may even replace them when the proper scientific
equipment is lacking.

Naturally, many of these tests were suggested to
us by lacquer consumers themselves; in many cases they represent specifications
that had to be
met, and since they came to our attention in this way, we feel that
they may be of interest to other lacquer users, who may not be familiar
with
them.

Let
us consider first clear lacquers as distinguished from pigmented lacquers,—lacquer
enamels. What qualities will the electroplater hope to find in a clear
lacquer? First,
I should say, would come adhesion.
If the lacquer is not going to stick, and stick hard and fast to the
surface to which it is applied, there is very little point in applying
it in the first place.

A very simple test, and a very significant test
for this quality is this: Flow the lacquer in question down on a piece
of metal, preferably beside
a lacquer known to have satisfactory adhesion. Put the metal plate
in the oven at about 150-175 degrees F. for about ten minutes; then when
the metal is cool, simply cut the lacquer away from the metal with
a
sharp knife. Lacquers have not yet reached a point where they cannot
be cut by a good knife; but a really adhesive lacquer will resist the
cutting, and will come away from the metal only where the knife actually
cuts it away. A lacquer without the proper adhesion will come away
all along the line of the cut in a jagged, irregular line, the film in
the
immediate neighborhood of the cut being removed also. If the lacquer
film coheres together to a greater degree than it adheres to the metal,
it may be removed in a sheet from the line of the cut. This brass sheet
will serve to illustrate this point. (Shows brass sheet.)

Immediately
after this prime factor of adhesion, and closely coupled with it, is
the question of flexibility. Metal lacquer users in general
(no one more so than those in the electro-plating industries) are coming
to realize that flexibility in a lacquer is a point which cannot be
overlooked, even when the lacquered object is not subjected to bending.
Flexibility
is the quality which enables a lacquer to resist chipping and flaking;
flexibility in a lacquer, coupled with adhesion, is the quality which
enables your product to withstand hard usage. Of course, the use of
really flexible lacquers often enables the manufacturer to save considerable
time and labor by doing his lacquering in the sheet, and any blanking
and forming required subsequent to the lacquering. A little later,
in
discussing lacquer enamels, I should like to bring out this point a
little more fully. At this point I wish to bring to your attention a
test for
flexibility which was suggested to us by a manufacturer of clock dials.
The dial is of brass, silver plated, and then lacquered in the sheet.
The blanking and forming operations are then performed. Then as a test
for flexibility the dial is placed in an acid copper bath, and this
acid copper bath tells a very interesting tale. When the lacquer is really
flexible, it is not at all injured; but where it is the least bit brittle,
it has chipped away, and the copper has plated out on the dial. This
test will detect lacquer failure even where it is not actually apparent
to the eye.

With
adhesion and flexibility considered, the next point to consider in
a lacquer is body. This quality should
not be confused
with
viscosity.
It is quite possible for a lacquer with high viscosity to have very little
body. The body of a lacquer depends upon the actual solid material in
the lacquer. These are the ingredients, of course, which actually do
the work of protecting the surface upon which the lacquer is applied.
With an analytical balance at his disposal, one may actually determine
the body of a lacquer, and express it numerically as percent solids.
Without such equipment, however, it is possible to obtain a very good
idea of the relative body of a lacquer in this way: First, as a control,
use a lacquer which is known to have satisfactory body. Then, in comparing
it with another lacquer, thin the two down to the same viscosity, then
flow them down, side by side, on a piece of metal. When they are completely
dry, the actual solid material present in each lacquer may be easily
compared by observing the thickness of film left in each case. The lacquers
in these two tubes (exhibiting tubes) while quite different in viscosity,
have actually the same body. When the more viscous is thinned down to
the consistency of the thinner one, and the two flowed out, the difference
in body at the same viscosity is readily apparent. The only fair way
of comparing the body of lacquers is at uniform viscosity. At this point
I should like to mention that, while body is an important consideration
in evaluating a lacquer, it should be borne in mind that high body is
only desirable when the first two qualities I have mentioned—adhesion
and flexibility—are also present. In other words, rather sacrifice
a percent or two of solids than the slightest degree of adhesion or flexibility.
Body is only a factor in rating two lacquers when the adhesion and flexibility
are comparable and in special cases where extreme thickness of coat is
required to protect the work.

These
qualities I have mentioned are, in general, the most important in rating
clear lacquers. There are, of course,
several others,—lustre,
flow and drying time—but these are qualities which may be easily
observed with a few moments’ work with the lacquer, and there are
no tests for these qualities more reliable than the spray man’s
eyes and experience.

Before
leaving the subject of clear lacquers, there are one or two tests for
special purpose lacquers which may prove
of
interest. The rather
mysterious phenomenon called ”spotting out” is a bugbear
in the lacquered metal industries. A quick test to gauge the resistance
a lacquer will offer to this type of failure is performed this way: A
piece of lacquered brass or silver is simply heated over an open flame,
heating gently so that only a slight, gradual discoloration of the surface
is effected. If the lacquer has a tendency to cause the metal to ”spot
out,” the spots will show up very quickly in this test. Any lacquer
will discolor in this test, but the discoloration should be uniform,
and free from spots.

In the field of silver lacquering, a very interesting
test, suggested to us by a manufacturer of shoe buckles, is performed
in this way:

The
silver plated article is finished in the usual way, by spraying or
dipping, and when it is dry, it is placed in an oven at 125 degrees F.
with a rubber band-around it, for several hours, or over night. At
the
end of this time, if the lacquer has not properly protected the silver
surface, the sulphur compounds in the rubber will have permeated the
lacquer film and discolored the silver. This is a very practical test,
since it is contamination from sulphur compounds in the air and the
human skin or in packing materials which causes silver articles to tarnish
and turn black, and in this test the extent to which a lacquer will
retard
this action may be gauged. This test may be run also with silver in
the flat sheet, substituting a flat piece of rubber for the rubber band.
I have here (exhibiting specimen) a piece of silver plated brass, which
has been lacquered on one half with one type of silver lacquer, and
on
the other half with a second and unsatisfactory silver lacquer. A piece
of rubber was placed on the metal, just over the intersection of the
two lacquers, so that it partially covered each of them. A piece of
tissue paper was placed between the two, to prevent their sticking together,
and they were placed in the oven at 125 degrees F. over night, in the
morning the extent of discoloration being observed. It will be noted
that while one half of the sheet retains practically the same color
it
had before the test, the other is badly discolored where the rubber
was over it.

I should like to call your attention to the number of tests
in which an oven is used. A good oven is an extremely useful asset in
the
testing
of lacquers, especially in testing for permanent flexibility. In an
oven the brittling effect of months of ageing can be obtained in a few
hours.

Passing
now to the consideration of lacquer enamels, the tests which have been
outlined for clear lacquers are, in many cases, equally adaptable
for testing lacquer enamels. Adhesion and flexibility are prime factors
in good enamels, just as they are in clear lacquers. The extreme flexibility
demands which some users of lacquer enamels make on their finishing
materials, make imperative the use of a quick test for this characteristic.
For
instance the manufacturer of these metal racks (exhibiting rack) for
the display of spools of thread, first applies the black enamel by
means of a coating machine, and does all his blanking, forming and crimping
after the lacquer is dry. It is obvious that no ordinary lacquer enamel
would suit his purpose; he could use a quick test for flexibility in
lacquer enamels. Another process in which extreme flexibility is required
is in the finishing of metal strip. The steel strip is first lacquered,
and then the very severe blanking and punching operations are performed.
Here again, a quick test for flexibility would quickly eliminate from
consideration the many lacquer enamels which would fail in this process.
A certain manufacturer of aluminum foil does his lacquering enamelling
first, and then the embossing needed for label work is done. Here is
another case where the flexibility demands are extreme. In all these
cases, the desirability for a simple flexibility test is evident; one
that will not require that the machines be set up or large quantities
of lacquer obtained for an actual plant test. Just such a simple test
has been devised. It consists merely of flowing down the lacquer enamel
on a piece of metal, baking, and when cool, cutting through the film
with a pair of shears. If the lacquer flakes away from the cut, or
if
it peels away, any of the manufacturers I mentioned above will know
that there is far less chance of the lacquer standing up under their
tests
than if the lacquer adheres just as firmly at the cut edge as it does
on any other part of the surface. This panel (exhibiting panel) will
serve to illustrate this point. As far as the drawing operations are
concerned, any die will reveal as much about a lacquer enamel in a
few moments as any expensive ductility machine. A certain manufacturer
of
bathroom fixtures has his own test for flexibility. Parts of these
fixtures are composed of wire, and this wire being the most flexible
part of the
fixture, he lacquers the wire and lets it stand around for three months.
This is longer than most of us care to wait for our results, but the
results when obtained are very gratifying and reassuring.

Body in the
lacquer enamel field holds the same position it does in the field of
clear lacquers. It is an important factor in the building of
good lacquers, provided it rests on a firm foundation of adhesion and
flexibility:

For the other general qualities a good lacquer enamel should
have, lustre, flow, etc., we must simply depend on our eyes and experience.

There is
one phase of this subject which I should like to touch on before closing,
and that is the proper attitude which should exist between the
users of lacquers and the manufacturers, in regard to tests and specifications.
In former times, it was considered good policy for the lacquer manufacturer
to keep the consumer as much in the dark as possible regarding lacquers,
and on the other hand for the user not to reveal what tests it had
to pass, or just what he expected from it in the way of service. This
attitude
militates very strongly against real progress and is now rapidly disappearing.
If the lacquer manufacturer can know in advance just what is expected
of his product, much time can be saved, and many headaches averted
by both parties. A case of our own, serving to illustrate this point,
occurred
in the case of a manufacturer of collapsible tubes. One manufacturer
had been getting his lacquer at rather high viscosity, and was applying
a very heavy coat to his product. A second manufacturer, making the
same type of product, had an entirely different idea of the correct way
to
finish tubes. He was trying to apply a very thin coat, practically
printing the lacquer on his tubes, and the material with which the first
manufacturer
was obtaining good results was entirely unsuited to him. He needed
a lacquer at a very thin viscosity, but we were not aware of this until
several unsatisfactory tests had been made and considerable time lost.
If we had known at once just how the lacquer was to be applied, much
time would have been saved, and the desired results obtained much sooner.

I
cannot make my plea for this closer, franker relationship between buyer
and seller too strong. The lacquer manufacturer has, or should have,
the technical knowledge necessary for the compound of good lacquers;
the lacquer user is familiar with the failings common to lacquers,
and the requirements which he must find in a lacquer; without a knowledge
of both sides of the question, the production of really successful
lacquers
is impossible. Therefore, if we both approach the question on an even
footing, if the lacquer manufacturer can know beforehand just what
his product will be required to do, many of the problems which today
perplex
both the makers and the users of lacquers will be solved, with highly
beneficial results to all parties concerned.

(Applause. )

DR. E. B. SANIGAR: Most of your tests, I take it, would
be affected by the cleanliness of the brass upon which you make them?

MR. KIRK: Yes,
certainly the brass has to be properly cleaned in all cases. I am taking
that for granted.

DR. SANIGAR: That is really an essential
point of the test.

MR. RAYMOND
LOPEZ: Have you made any perspiration tests? For instance, take an
article with a handle which is used a great deal; there is a
tendency, if the lacquer is not satisfactory, for the perspiration
to penetrate to the silver or brass, whatever it may be.

MR. KIRK: That is
a very difficult situation to duplicate without some chemical equipment.
That can be done with moist hydrogen sulphide, for
instance, in a dessicator, but that requires laboratory equipment,
and I was trying to confine myself entirely to tests that could be made
in
the shop. We have done that; that is a good test for silver and brass
lacquers, but it requires chemical equipment.

MR. LOPEZ: Well, we do that
with a dessicator, but I thought perhaps you might have a practical
test where it could be done without instruments.

(Session adjourned.)

THE PROTECTIVE VALUE OF A COPPER STRIKE

BY
W. S. Barrows
Read at Washington Convention, 1930

Twenty years ago, the question of
the advisability of copper plating steel or iron previous to nickeling
was a common one among platers. It
was usually regarded as good practice on sheet steel, steel tubing,
forgings, etc., but inadvisable on cast iron. If the process was eliminated,
it
was generally due to economic reasons rather than because it was considered
useless from the standpoint of producing more durable protective coatings.
Nor was the copper strike discontinued, but copper undercoatings generally
received the taboo in many plants.

Within the past ten years, motor car
trimmings of steel have been finished with only a nickel coating averaging
in thickness between 0.0001 and
0.0002 inch.

Naturally such coatings were productive of much dissatisfaction
to both the manufacturer and the buying public. Within the past five
years, copper
coatings of at least 0.0003 inch, followed by nickel at least 0.0003
inch thick, have been specified. Furthermore, the deposition of nickel
directly upon the steel, followed by copper and a subsequent coating
of nickel, has been favored by many, and regarded by some as the final
word in combining nickel and copper deposits for protective purposes.

One
writer has stated, ”If copper plated steel is to have only
a thin protective coating, and does not require buffing, 10 to 15 minutes
will suffice. If the surfaces are to be buffed after nickeling, then
30 to 60 minutes will be required to produce a sufficiently heavy nickel
coating; 8 to 10 amps. per sq. foot at 3 or 4 volts.”

Thirty years
ago, we employed the cyanide copper bath for the production of a mere
flash of copper previous to nickeling steel surfaces, but the
nickel coatings were seldom less than 0.002 in. thick, and the protection
afforded to steel of that period was in general quite satisfactory.
We polished good steel surfaces in those days; today we merely skim over
the surface of exceedingly inferior steel with one wheel, and leave
innumerable
pits, cavities and inclusions which present an altogether different
condition for treatment by the plater.

In an attempt to determine the best method
of using copper and nickel on extremely soft, porous sheet steel of
25 gage, which was to be used
in the manufacture of a product which would be subjected to a wide
range of climatic conditions in various parts of the world, I began a
series
of tests which as yet unfinished have proven rather interesting, and
give promise of some really helpful information. The tests were conducted
in four series:

Series
A—Total deposits produced in
less than five minutes.

Series
B—Total deposits not less than 5 min. or more than 10 minutes.

Series
C—Total deposits not less than 10 min. or more than one
hour.

Series
D—Total deposits over one hour.

Fabricated parts were taken
at random from stock in process. The surfaces of each sample were used
in the tests. All samples were prepared in the
same manner up to point of introduction to dip preliminary to plating.

In
Series A, results were practically the same on samples nickeled direct
for 1 minute and on those nickeled direct for 4 minutes at the same
current density.

Gave 50% better
production than a 3 minute deposit of nickel direct on steel. Pits
in all samples were enlarged, areas around pits were corroded.

In
Series B, samples nickeled direct 5 min. at 10 amps. per sq. ft. bath
temp. 90 were corroded over 95 per cent of surface. 10 min. nickel
direct was corroded over fully 50 per cent of surface.

Samples which received
Ni-2 min., Cu-1 min., Ni-2 min, C. D. for nickel being 20 amps. per
sq. ft., and C. D. for copper being 150 amps. per
sq. ft., corroded only at pits, edges of pits were sharp and clean,
surrounding areas not affected.

In Series C, where the minimum deposit was
10 min. and maximum deposit was 60 min., we obtained contradictory
results. Samples which received
deposits of nickel direct for 60 min. were corroded over 60 per cent
of areas and surfaces surrounding pits were seriously affected.

Ni-3
min., Cu-3 min., Ni-15 min. was affected over only 10 per cent of surface,
while Cu flash or approximately 5 seconds, Ni-60 min., was seriously
attacked over fully 75 per cent of surfaces.

Not until we began Series
D (deposits of over 60 min.) did we obtain anything which gave evidence
of being sufficiently durable to meet even
local climatic conditions satisfactorily. In this series the samples
were treated by various methods to ascertain the value of such special
manipulations.

}

}

Equally as good condition as
No rust or other indication of attack at pits.

}

Ni-10 min.
Cu-10 min.
Wire brushed
Ni-60 min.

Cu-30 min.
Buffed
Ni-2-1/2 hrs.

—30 amps. sq. ft. Bath temperature 120° F.

— 5 amps.
sq. ft. Bath temperature 70° F.

These
samples were almost perfect. Two or three pits defied protection by
the coatings. Copper was exposed around these pits, but steel was
not exposed or attacked; otherwise surfaces were in splendid condition.

The
next record does not indicate that the experimenter became affected by
the heat or obsessed with the idea of ”repeat the operation,” but
it does indicate to what extent we diversified our methods.

These samples were the only ones accepted as sufficiently
perfect. The pits were sealed, not a trace of corrosion was detected
after 308
hours
in salt spray and subsequent exposure of 6 months on roof of factory
directly in front of fan outlet from plating department.

Therefore, at
this point in our experiments we are hopeful of producing a protective
coating of copper and nickel which will afford satisfactory
protection to steel surfaces in any climate permanently endured by
man, if we can invent a contraption which will alternate plating and
brushing
operations without aid of manual labor.

Copper strikes of the flash order
did not prove beneficial. Copper strikes of one minute duration did prove
of value.
Initial deposits of nickel, followed by a copper strike of 1, 2 or 3
minutes’ duration, did not give greater protection than initial
coatings of copper followed by nickel deposits approximately one-third
thicker than in the former instance.

On good
clean steel surfaces, free from pits, cavities or inclusions, the samples
given 1 min. and 2 min.
copper strike at 150 amps. per sq.
ft. in a bath at 120° F. were decidedly more resistant to salt spray
and exposure tests than samples given 30 seconds copper strike or nickeled
direct on steel.

The copper solution employed in these tests is one which
was made by removing 75 gallons of an excessively dense cyanide copper
solution and
diluting the 75 gallons to make 150 gallons. At time of tests the free
cyanide content was 1.1 oz. per gallon, and the metal content was 3.25
oz. per gallon.

Nickel
deposits were obtained from one bath only at a C. D. of 20 amps. per
sq. ft. with bath temperature of 90,
except those
where 5 amps. per
sq. ft. and temperature of 70° F. are given.

Copper
deposits were obtained with current densities ranging from 30 amps.
per sq. ft. to
180 amps. per sq. ft. according to duration of plating;
solution temperatures ranged from 120° F. to 150° F.

We found
that if the object being plated was repeatedly placed on a holder in
the same position, regardless of how many times the coatings were
alternated, the results were inferior to deposits obtained on specimens
which were hung in different positions following brushing, buffing
or plating operations. All samples tested were plated singly on a brass
hook with perforations which facilitated quick change of position.

In
conclusion, a consistent copper strike followed by a consistent nickel
deposit is undoubtedly of much protective value. A copper flash beneath
a thin deposit of nickel is not only useless as added protection, but
seems to reduce the protective value of the combined coatings.

We have
not aimed at originality in this paper, but have tried to record facts
as they were revealed. Furthermore, the statements made are not
conclusive. We are continuing tests and experiments.

CHAIRMAN
GEHLING: Now, members, I think we can afford to allow, on a paper of
that sort,
at least ten or twelve minutes’ discussion,
but at the end of that time we want to cut it off because we want to
get into our business session at 10:15 sharp.

MR. S. P. GARTLAND. I would
like Mr. Barrows to inform us if that would be a good procedure on
cast iron, to copper plate it for five minutes,
brush it, and copper plate and brush it, that is, to go through the
series three times, and then nickel deposit on that for say fifty or
sixty minutes.

MR.
BARROWS: I would say yes, if you do not use too high a current density
on your initial coating. I have had experience,—I remember one
instance in particular, in gas engine cylinders. This was some time ago.
They were having considerable trouble with gas engine cylinders. It seems
the procedure at that time among job shops in particular was quite contrary
to the procedure which we were employing, and repeatedly met with failures,
and they turned the job over to our firm, and we attempted to go ahead
with it, and by employing a copper solution of low density,—in
fact, I believe at that time we only used a hydrometer, and I believe
the hydrometer reading was something like three or four, never exceeding
five, and using a rather low current density, we had no difficulty at
all. And some of those cylinders are in use today.

MR.
PHILIP SIEVERING: I would like to ask Mr. Barrows what procedure he
took in cleansing the
metal before plating,—scratch brushing,
pickling, or otherwise, in order to get the pits clean.

MR.
BARROWS: This material was a very, very soft sheet steel. It was not
purchased for
finishing by nickeling; it was purchased for a second
grade enamel job, and was not really intended to be used for electroplating
at all. But they were forced to turn out several hundred thousand pieces
with a nickel finish, and the job was turned over to me, and I bumped
up against this pit proposition. As the stock came to us from shearing
and stamping, it was racked and run through a soap solution, just briefly,
through an electric cleaner composed of one of the common metal cleaners,
this bath being maintained as near boiling as possible,—taken from
the electric cleaner and plunged into a 4% solution of sulphuric acid
and water, rinsed, hung in a cyanide bath, and then if copper was to
be the next operation, copper plated. There was no brushing. Although
we did tumble some of the pieces toward the latter part of the work,
just briefly. That was before putting in the electric cleaner or the
soap. In fact, we then omitted the soap. It was just passed through a
dilute hydrochloric acid, rinsed and went directly into the nickel. The ”skin,” as
we call it, was not removed from the metal; and it was very, very thin,—there
were no polishing operations.

MR.
KREIDEL: I would ask whether using a higher amperage, higher voltage,—higher
density all around, would be a better protection on a short duration.
I believe it is common practice for at least job shops to use a higher
current density for the strike.

MR. BARROWS: 180 was the highest we went.
That was just a brief strike, 5 minute strike, generally around 120
or lower. About 32 or 4 volts,
at the tank.

MR.
F. HAUSHALTER: I would like to ask the gentleman who just spoke there
on copper solution used on cast iron
cylinders, with
a hydrometer reading
of 4 or 5, —well, that kind of leaves us in the dark. The thing
is, what was the copper cyanide, or the carbonate?

MR. BARROWS: That was
some years ago, before I had used anything else other than a hydrometer.
It was made up from copper carbonate.

MR. HAUSHALTER:
There would be a difference, you know, in the metal content in that,
using copper cyanide.

MR. BARROWS: It was a copper carbonate
solution.

MR. C. J. WERNLUND: I
would like to ask Mr. Barrows what is the minimum weight of copper
plate you would recommend under nickel for a good quality
plate?

MR.
BARROWS: I couldn’t tell you; we haven’t gone into
it. In fact, this work was done simply to get this job finished satisfactorily,
and a great deal of data that I would have taken, had I been preparing
a paper, or had any idea of preparing a paper, I should have included,
was neglected. But I had no intention of reporting anything like this;
I simply picked this up from data that I casually obtained as I went
along. But to my way of thinking, I wouldn’t be afraid of getting
too much. Not on a line of work such as this. My firm ships goods to
practically all parts of the British Empire, Japan, China, Straits Settlement,
New Zealand, Fiji Islands, and elsewhere. In fact, we are now going into
the European markets, and we have to meet a great variety of climatic
conditions.

MR. FEELEY: Do you feel that there is greater security
in the direct deposition of copper on the steel than you do the nickel?

MR.
BARROWS: I don’t say that, no sir.

MR.
FEELEY: Because I know from job shop experience for many years we always
copper plated cyanide
until some six or seven years ago Dr. Blum
happened to be in Montreal, and drew our attention to nickel plating,
and in our bumper work of course it is a job shop proposition of quality,—we
generally deposit half a thousandth of nickel and about two thousandths
of copper, and buff on the copper and put on a thousandth of nickel.
And I can safely say that we are having wonderful success from that.

About
eleven years ago, prior to that, we did copper plate; we ran around
two and one half to three thousandths at that time from cyanide copper
on steel, scratch brushed a couple of times, and then we silver plated,
when we were doing any silver plating, and then we silver plated the
radiator shells, silver plated bumpers, and burnished them. After eleven
years in Montreal, we still have some radiator shells that had been
silver
plated along that line, and are as good today as they were at that
time.

MR.
BARROWS: I don’t even claim that the method that we found successful
is practical; in fact, I wouldn’t consider it practical in our
own plant; I wouldn’t attempt it. But (and this is not presented
with the idea of making any claims or anything like that) we just simply
present the paper as a record of what we have done.

MR. FEELEY: How would
you handle that same job if you had it to do over again tomorrow?

MR.
BARROWS: I would use alternate coatings, but I would endeavor to get
thicker deposits as I went along. In fact,
we did that
along towards
the latter part of our work. It was a little too frequent, that stuff.
In fact, after we found how we wanted to do it, we did it in the sheets,
instead of using the pieces. We went so far in the sheet and then cut
it. That did leave the edges with less protection, but due to the fact
that the piece was more or less protected at the edges, we got away with
it; at least we hope we did. We don’t very often try to do anything
like that.

A. E. S. PAGE
Assembled Expert Scraps With and Without Significance

Do you know that:We mailed 1600 copies of the MONTHLY REVIEW last month?

Do you know that:This page will soon be devoted to the activities of the Platers Classes,
the Research Committee, the Board of Education, and the new ideas you
are going to send in to increase the prestige of the A.E.S.?

Do you know
that:Our constitution lays down hard and fast rules regarding our officers,
both in the Supreme Society and in the Branches, but allows each individual
member the privilege of shaping his destiny without any ”do’s” or ”do
nots”?

Do you know that:Each member owes a moral obligation to the Society and although
we have no oath of allegiance to bind us, we are in duty bound to boost
our Society —attend
the meetings—pay our dues promptly—help the other fellow
carry his burden—and give our employer the best that is in us?

Do
you know that:A number of copies of the REVIEW are sent to London, Birmingham,
Sheffield, and other parts of England; and that the Canadian Bureau of
Mines wrote
the Editor last month saying, ”We are most desirous of keeping
this valuable file intact”?

Do you know that:During the Round Table discussion at the Washington Convention,
a member of Milwaukee Branch related in dramatic fashion the experiences
he and
a number of his fellow members had in trying to start a class for platers?
He concluded by saying that ”not having a definite program and
a capable instructor their efforts were well nigh wasted.” With
the perseverance Dan Wittig has shown it is safe to predict that Milwaukee
Branch will be amongst the first to fall in line with the new order of
things and will rise from seeming defeat to heights of achievement that
will make our whole membership glad.

Do you know that:
“The heights by great men reached and kept
Were not attained by sudden flight,
But they while their companions slept
Were toiling upward in the night”?

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